A substantial portion of the translation cycle of the moving reflector(s) in a Michelson interferometer is required for direction reversal. Reflector turn around is conventionally effected simply by abruptly applying a strong reverse current to the drive motor; this technique results however in unnecessary travel and makes resumption of the correct, constant speed difficult to achieve. Since scanning cannot be carried out during the period of reflector reversal, the motion and time that are lost in that phase of the cycle represent primary limitations upon interferometer speed, and hence upon the performance of any instrument that incorporates the interferometer.